True Coincidence Summing Correction in Gamma Spectroscopy

Germanium is the most commonly used detector material for its higher atomic
number (as compared to Silicon) which makes it practicable for detection of higher
energy gamma radiation. Over recent years, the technology for the manufacture of
high purity germanium with a suitable degree of crystal perfection is achieved. When
an n+ layer is created on a face of a high-purity p-type germanium slab (Figure-1.2)
and a reverse bias is applied to the detector, a depletion layer throughout the p-type
material is formed. Such a detector is called hyper-pure or simply high-purity
germanium detector abbreviated as HPGe.
Figure 1.2 The basic construction of germanium detector. [1]
HPGe detectors are available in a number of different configurations to suit particular
situations. Figure-1.3 shows the simple standard forms together with an indication the
energy range over which they might be used.
Figure 1.3 Configuration of detector generally available together with the used energy range [3]
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